Sound box for sound-reproducing machines



April 3, 192a. 1,664,591

A. CLOT SOUND BOX FOR SOUND REPRODUCING MACHINES Filed May 3, 1927 a as 5f A0605 7'06 C107",

gin 00114101 PATENT OFFICE.

AUGUSTUS CLO'I, 03 WEST NEW YORK, NEW JERSEY. Y

SOUND 1101 FOR SOUND' REPRODUCING MACHINES.

Application filed Kay 3,

My invention relates to improvements in sound boxes for sound reproducing ma.- chines.

An important object of the invention is to provide a sound box of the above mentioned character, so constructed that the sounds are reproduced. with the maximum accuracy, and

. music, vocal or instrumental, is cantabile, with the full and proper reproduction of the low notes or basses.

A further ob'ect of the invention is to provide a sound it so constructed that the flexible dia hragm is held under suitable tension, witll its maximum area free for vi-. ll bration, whereby the device will roduce the sound in its maximum fullness, or the size or diameter of the dia hragm.

A further object of the invention is to rovide a device of the above mentioned c aracter which is of simple construction with its parts arranged in a highly compact mannot.

A further object of the invention is to provide simple and reliable means to adjust the dia hragmfor maintaining the same under tile proper degree of tension.

A further object of the invention is to provide a sound box which will improve in tone. with age.

Other objects and advantages of the invention will be ap arent during the course of the following description.

In the accompanying drawings forming a part of this specification, and in which like numerals are em loyed 'to designate like parts throughout t e same, I F'gure 1 IS a side elevation of a embodying my invention,

Figure 2'is an elevation of side of the same,

Figure 3 is a transverse sectiomtaken on line 3--3 of Figure 1, upon an enlarged scale,

Figure 4 box,

F i'gure 5 is a horizontal section, taken on line 55 of Figure4,

Figure 6 is a detailed section, taken on line 66 of Figure 1, and,

Figure 7 is a fragmentary radial section, upon an enlarged scale, through the shell Y 'ng and diaphragm. T drawings, wherein for the purpose "on, is shown a preferred embodi- TVel'ltlOfi, the numeral 10 desigsound box the opposite is an edge elevation of the sound 1927. Serial Io. 188,496.

nates a shell or casing, circular in cross section, and tapered in one direction. At its outer end, this casin has a cylindrical periphcr 11, with its .orward and rear edges 12 an 13 sli htly rounded The shell 10, at its reduce end, leads into a cylindrical neck or reduced extension 14, adapted to be inserted upon the tone arm of the horn of a sound 'reproducing machine, of anywell known or preferred construction. The neck a 14 is clamped to this tone arm by means of g -.a set screw 15, or the like.

Surrounding the tapered shell 10 is a tension ring 16, of slightly larger diameter, and this tension ring is provided with inwardly projecting radial apertured cars 17, having ,screw-threaded engagement with tension screws 18,- which en age the rear concave face of the shell 10. hese screws are ui-' distantly spaced and I preferably emp 0y three or more of them.

The numeral 19 designates a flexible diaphragm, formed of fibrous-material, and I preferably employ a membrane, such as sheepskin, while I may employ parchment or other suitable fibrous material. The flexible diaphragm 19 has its material passed over the periphery 11 of the shell 10 and engages with the slightly'rounded ed e 12, while the vibrating ortion of the diaphragm is spaced from t e shell 10 at all points inwardly of the shoulder 12, whereb the maximum vibrating surface is obtainable for a diaphragm of given diameter. This is an im ortant feature of the invention as it contri utes to the fullness and accurac ofthe sound reproductiom The materia of the diaphragm, at its edge, is now carried into an, annular groove or recess 20, tormed. in the periphery of the tension ring 16, and is tied or securely bound within this groove by cord 21 or the like. The diaphragm may be also glued or cemented to the wall of the groove 20, in addition to the tying action, if desired. It is preferred that the material of the diaphragm be securely anchored within the groove 20 so that'there will be no possibility of such material slipping within v thegroove.

The neck 14 is preferably provided with a flattened portion 22, having the inner or upper end of an Lshaped bracket 23 secured theretob screws 24 or the like. At its lower end, the racket 23 is provided with a transverse bridge 25, preferably formed integral, no

therewith. This transverse bridge has lateral extensions 26, at the ends thereof, projecting in opposite directions. The bridge 25 is provided near its ends with dependm knife edge pivots 27, rigidly I attache thereto.

Arranged beneath the bridge 25 is a transverse vibratory bar 28, provided on its upper surface, near the ends thereof, wlthgrooves 29, which are V-shaped in cross section and receive the knife edge pivots 27,

.opposite end portion of this clip is bowed .and is arranged beneath the extension 30, and is provided with a raised lug 33, to enter a recess in the lower surface of the extension 30. These spring clips are oppositely faced, and have, the same strength or tension and, therefore, their force upon the vibratory bar is balanced.

The vibratory bar is provided near its center with a laterally projecting arm 34, having rigid connection with a vibratory lever 35, extending radially of the diaphragm l9 and positively attached to the diaphragm, at the center of the diaphragm, by means of a rivet 36 or the like. This point of attachment is concentric with the edgel2 and hencethe edge of the vibratory area of the diaphragm.

Rigidly secured to the vibratory bar 26, at its'centelyis a tube or socket 37 depending therefrom, adapted for the reception of a needle or stylus 38, held Within the socket by a set screw 39 or the like.

In use, the needle is placed in contact Withthe record, and the vibrations transmitted to the needle are transmitted to the dia-i phragm 19, through the medium of the lever 35 and associated elements. The entire vibratory area of the diaphragm, within the edge 12, is free from contact with the shell 10, and 'hence the maximum vibratory area is obtainable. it is highly desirable that the diaphragm be maintained at the proper tension, and when the tension is to be adjusted, such as when it is desired to restore the proper degree of tension to the diaphragm, the screws 18 are turned in a direction to cause the ring 16 to move away from the shell 10. All of the screws should be turned for about the same extent, so that the pull upon'the diaphragm will be equal in all directions. and there will be no tendmeteor ency for the diaphragm to become. eccentric with respect to the connection 36.

It is to be understood that the form of my invention, herewith shown and described, is .to be taken as a preferred example of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention, or the scope of the subjoined claims.

Having thus described my invention, I claim 1. A sound box for sound reproducing machines comprising, a shell flaring towar one end and having a contact edge at its periphery, a flexible diaphragm arranged at the large end of the shell and engaging with said edge, said engagement defining the vibratory area'of the diaphragm, which area is free from contact with said shell, a

stylus, and connecting means between the stylus and diaphragm.

2. A sound box for sound reproducing machines comprising, a shell flaring toward one end and having a contact edge at its periphery,a flexible diaphragm arranged at the large end of said shell and engaging with said contact edge, said engagement defining the vibratory area of the diaphragm, which area is free from contact with said shell, adjustable means to re ulate the tension of the diaphragm, a sty us, and connecting means between the stylus and diaphragm.-

3. A sound box for sound reproducing machines comprising, a shell which is circular m cross sect1on and increases in dlameter in one direction, a flexible diaphragm arranged at one end of the shell and engagmg the perlphery of the same, a tension rin surrounding thereduce'd portion of the she I and connected with the diaphragm, and adprstmg screws carried by the tension ring and engaging said shell, a stylus, and con- I its periphery, means for binding the edge of the diaphragn'i within lhegroove of said ring, adjusting screws carried by the ring and engaging the rear side of the large end of the shell, a bracket carried by the shell, a stylus pivoted upon the bracket, and a lever connected with the stylus and with the diaphragm.

In testimony whereof I aflix my signature.

AUGUSTUS CLOT. 

